Britax Grow With You Harness-2-Booster - Mod Black | live price, prepared checkout

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• Deep research: We read the maker's manual, independent reviews, video review transcripts and the store's own page, and publish each finding with its source and the date read. check_product returns them with a source for each. This product: 39 checked facts, research depth trimmed read, checked 2026-10-13T00:34:00.458Z, in the evidence pack.
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Checked facts

Each fact below was checked against the source it cites before it was published. Each carries that source's link and the time RoboTrunk read it. 39 checked facts, checked 2026-10-13T00:34:00.458Z. Research depth: trimmed read. Deep read: the store's own data and 9 outside pages (the store's own product page; maker page; manual; regulator recall search (CPSC (United States)); regulator recall search (Health Canada); official safety test results (CREP, the Child Restraint Evaluation Program); official safety test results (NHTSA's Car Seat Ease of Use Ratings); official safety test results (ADAC's child seat test)), each read in full by RoboTrunk and trimmed to its main content, then written up and checked. Facts from the maker or a manual quote the page word for word; what real users report is summarised with a link to the page read. Recall status was checked directly with CPSC (United States), Health Canada: A CPSC recall search for this manufacturer and model returned no recall records, and the Health Canada list of 23 Britax records names no Grow With You model, listing other Britax child seats and strollers instead. Owners are still told to register the seat so they can be reached if a recall is issued. Official safety test results were looked up directly with CREP, the Child Restraint Evaluation Program, NHTSA's Car Seat Ease of Use Ratings, ADAC's child seat test: CREP, the Child Restraint Evaluation Program (Australia and New Zealand): CREP's published list of 216 tested seats is complete and contains no Grow With You Harness-2-Booster; its Britax entries are all Britax Safe-N-Sound seats sold in Australia and New Zealand. NHTSA's Car Seat Ease of Use Ratings (United States): The list includes a Britax Grow With You with model number E1C449H (rated seat made 2021-06-01), a different model from this seat's E1C442T, rated 5 of 5 overall forward-facing and 3 of 5 overall in booster mode. These are ease-of-use ratings, not crash-test results. ADAC's child seat test (Germany, the UK and Europe): ADAC's published list since 2015 is complete and contains no Grow With You seat; its Britax entries are all Britax Römer models. Not read, because they are member-only or refused RoboTrunk: Consumer Reports car seat ratings, Which? child car seat tests, JPMA certified products.

• weight limits: Sources disagree on harness limits: the store feed lists 25–65 lb, and the 2021 manual lists 25–65 lb and 34–49 inches; Strolleria's product-page description instead lists 30–65 lb and 35–49 inches and says limits vary by model, so follow the seat's own labels and user guide.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• fit: This store's page states harness mode is 30-65 lbs and 35"-49", which differs from the manual's 25-65 lbs and 34"-49".. Source: https://strolleria.myshopify.com/products/britax-grow-with-you-convertible-car-seat-mod-black (guide), read 2026-10-13T00:11:11.295Z.
• installation: The maker lists premium quick-push LATCH connectors for simple, secure installation.. Source: https://us.britax.com/shop/car-seats/grow-with-you-harness-2-booster-car-seat/variant/3468381?bvstate=pg%3A4%2Fct%3Ar (guide), read 2026-10-13T00:11:15.714Z.
• fit requirements: The 2021 manual specifies harness use for children 25–65 lb, 34–49 inches tall and at least 2 years old; sources disagree because Strolleria's product-page description lists 30–65 lb and 35–49 inches and says limits vary by model, so follow the seat's own labels and user guide.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• recall: A CPSC recall search for this manufacturer and model returned no recall records.. Source: https://www.saferproducts.gov/RestWebServices/Recall?format=json&Manufacturer=Britax (guide), read 2026-10-13T00:11:49.079Z.
• recall: A Health Canada recall search returned 23 Britax records, none naming this model.. Source: https://recalls-rappels.canada.ca/sites/default/files/opendata-donneesouvertes/HCRSAMOpenData.json (guide), read 2026-10-13T00:11:49.462Z.
• weight limits: In forward-facing booster mode the seat is rated for children from 40 to 120 lbs.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• expiration: The seat expires after 9 years.. Source: https://strolleria.myshopify.com/products/britax-grow-with-you-convertible-car-seat-mod-black (guide), read 2026-10-13T00:11:11.295Z.
• expiration and warranty: The maker states a 9 year expiration and a 1 year limited warranty.. Source: https://us.britax.com/shop/car-seats/grow-with-you-harness-2-booster-car-seat/variant/3468381?bvstate=pg%3A4%2Fct%3Ar (guide), read 2026-10-13T00:11:15.714Z.
• fit requirements: Booster mode is for children 40-120 lbs and 44-63 inches tall.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• dimensions: The seat measures 21 x 19 x 25 inches.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• buckle: The buckle has two positions and a pad that flips forward out of the way for boarding.. Source: https://strolleria.myshopify.com/products/britax-grow-with-you-convertible-car-seat-mod-black (guide), read 2026-10-13T00:11:11.295Z.
• care: The removable SafeWash cover is safe to machine wash and dry.. Source: https://us.britax.com/shop/car-seats/grow-with-you-harness-2-booster-car-seat/variant/3468381?bvstate=pg%3A4%2Fct%3Ar (guide), read 2026-10-13T00:11:15.714Z.
• safety standards: The seat conforms to FMVSS 213.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• weight: One store lists the seat's product weight as 23 lbs.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• belt routing: Colour-coded belt guides are meant to make routing the seat belt correct and to help children learn to buckle up.. Source: https://strolleria.myshopify.com/products/britax-grow-with-you-convertible-car-seat-mod-black (guide), read 2026-10-13T00:11:11.295Z.
• storage: The maker lists 2 cup and snack holders with additional storage. One store's description instead says four cup and snack holders.. Source: https://us.britax.com/shop/car-seats/grow-with-you-harness-2-booster-car-seat/variant/3468381?bvstate=pg%3A4%2Fct%3Ar (guide), read 2026-10-13T00:11:15.714Z.
• aircraft: It is certified for aircraft use in harness mode but not in booster mode.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• care: The cover can be machine washed and dried instead of hand washed or air dried.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• weight limits: In booster mode the seat takes children up to 120 lbs and 63 inches tall.. Source: https://strolleria.myshopify.com/products/britax-grow-with-you-convertible-car-seat-mod-black (guide), read 2026-10-13T00:11:11.295Z.
• materials: Britax may substitute fabrics or parts and says the actual product may vary from the image.. Source: https://us.britax.com/shop/car-seats/grow-with-you-harness-2-booster-car-seat/variant/3468381?bvstate=pg%3A4%2Fct%3Ar (guide), read 2026-10-13T00:11:15.714Z.
• expiration: The seat must be retired after nine years or after a moderate or severe crash.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• materials: The fabrics and foam are naturally flame retardant with no added FR chemicals.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• LATCH limit: Lower anchors must not be used for a child weighing more than 45 lbs.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• safety features: The listed safety features are a steel frame, a crumple zone, a patented V-shaped tether and two layers of side impact protection around the head, neck and torso.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• installation: Britax recommends using the top tether at all times when installing the seat.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• warranty: The seat carries a 1 year limited warranty.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• orientation: The seat is forward-facing only.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• fit: Harness slot heights span 12 to 20 inches.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• warnings: Cover the seat when parked in direct sunlight because metal parts could become hot enough to burn a child.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• fit: The seat area measures 15 inches deep by 12 inches wide.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• warnings: Non-Britax covers, inserts, toys, accessories or tightening devices are not approved and could make the seat fail FMVSS or not perform in a crash.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• recline: The seat has a 2-position recline.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• registration: Owners must register the seat so Britax can reach them if it is recalled.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• safety technology: SafeCell technology in the base acts as a crumple zone to absorb crash energy.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• overhang: In harness mode up to 3 inches of the base may hang over the front edge of the vehicle seat.. Source: https://csus.britax.com/media/13025430/2021_p13130600_a_growwithyou_userguide_web-1.pdf (manual), read 2026-10-13T00:11:29.423Z.
• materials: The SafeWash cover is described as soft to the touch and its knit construction as naturally flame retardant.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• recommendation: Britax recommends keeping children in a harness until they exceed the harness weight or height limits.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.
• identifiers: The Mod Black variant's GTIN is 652182742836.. Source: https://strolleria.myshopify.com/products.json (listing), read 2026-10-12T20:06:05.806Z.

The full evidence pack, with every citation, source and gap.

Questions we researched but could not confirm

Every fact above is cited. To find them we read the store listing, the maker's page, the manual, the recall records of CPSC (United States) and Health Canada and the safety test results of CREP, the Child Restraint Evaluation Program, NHTSA's Car Seat Ease of Use Ratings and ADAC's child seat test and searched for regulator recall notices, owner reviews, blogs, owner forums and video reviews. We also chased the questions below across those sources and found no reliable answer, so you know exactly where the evidence ends and never have to guess.

• How does the fabric feel to the touch, and is it thin or thick?
• Does the cover's colour rub off or fade with use?
• Which specific vehicles has this seat been confirmed to fit?
• Will it fit three car seats across in a typical back seat?
• How long does installation take for one person?
• What tools are needed to install or assemble the seat?
• Does the booster shoulder belt guide let slack slip into the belt?
• How neatly does the harness store away in booster mode?
• Do the cup holders fit standard sippy cups and bottles?
• How does the cover hold up after repeated machine washes?
• How does the padding hold up on long journeys?
• What tends to break first with heavy daily use?
• Does the head restraint work with raised vehicle head restraints?
• Is a travel bag or carry strap available for this seat?
• How does its crash protection compare with the ClickTight version?

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